ORCID Profile
0000-0001-6622-9535
Current Organisation
University of Adelaide
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: AIP Publishing
Date: 05-2008
DOI: 10.1063/1.2919944
Abstract: We review the techniques used in the design and construction of cryogenic sapphire oscillators at the University of Western Australia over the 18year history of the project. We describe the project from its beginnings when sapphire oscillators were first developed as low-noise transducers for gravitational wave detection. Specifically, we describe the techniques that were applied to the construction of an interrogation oscillator for the PHARAO Cs atomic clock in CNES, in Toulouse France, and to the 2006 construction of four high performance oscillators for use at NMIJ and NICT, in Japan, as well as a permanent secondary frequency standard for the laboratory at UWA. Fractional-frequency fluctuations below 6×10−16 at integration times between 10 and 200s have been repeatedly achieved.
Publisher: AIP Publishing
Date: 07-2000
DOI: 10.1063/1.1150684
Abstract: The operation of a novel monolithic sapphire transducer from room temperature to cryogenic temperature is presented. The transducer is a microwave sapphire resonator that senses the motion of internal acoustic resonances through the interaction between electric and acoustic fields. The system is noncontacting and has low mechanical and electrical losses. Also, the microwave characteristics of sapphire are used as an inherent temperature sensor. High mechanical quality factors of 108 and 4.5×108 were attained at 300 and 4 K, respectively.
Publisher: Institution of Engineering and Technology (IET)
Date: 2006
DOI: 10.1049/EL:20063490
Publisher: Oxford University Press (OUP)
Date: 12-03-2012
Publisher: IEEE
Date: 2005
Publisher: IEEE
Date: 2005
Publisher: Elsevier BV
Date: 2007
Publisher: American Chemical Society (ACS)
Date: 22-04-2014
DOI: 10.1021/JE500083N
Publisher: Institution of Engineering and Technology (IET)
Date: 2003
DOI: 10.1049/EL:20030234
Publisher: AIP Publishing
Date: 15-12-1998
DOI: 10.1063/1.369023
Abstract: A sapphire monocrystal configured with a parametric microwave readout can potentially monitor the motion of its internal acoustic resonances at the precision governed by quantum mechanical fluctuations. The mechanism of transductance is due to parametric interaction between the electric and acoustic field within the crystal. This mechanism has been tested for the first time, and the theory has been verified by observing the pump frequency dependence of the acoustic quality factor. Because of the extremely low acoustic losses (Q& ) and electrical losses (Q& ), measurements were sensitive enough to attain positive verification at room temperature.
Publisher: IOP Publishing
Date: 07-04-2006
DOI: 10.1143/JJAP.45.2827
Publisher: Springer Science and Business Media LLC
Date: 10-02-2015
Publisher: IOP Publishing
Date: 14-07-1997
Publisher: Elsevier BV
Date: 08-2015
Publisher: World Scientific Pub Co Pte Lt
Date: 06-2000
DOI: 10.1142/S0218271800000219
Abstract: The International Gravitational Event Collaboration, IGEC, is a coordinated effort by research groups operating gravitational wave detectors working towards the detection of millisecond bursts of gravitational waves. Here we report on the current IGEC resonant bar observatory, its data analysis procedures, the main properties of the first exchanged data set. Even though the available data set is not complete, in the years 1997 and 1998 up to four detectors were operating simultaneously. Preliminary results are mentioned.
Publisher: American Chemical Society (ACS)
Date: 12-2014
DOI: 10.1021/JE500857W
Publisher: IEEE
Date: 2002
Publisher: IEEE
Date: 2001
Publisher: Springer Berlin Heidelberg
Date: 2006
Publisher: IOP Publishing
Date: 10-07-2002
Publisher: AIP Publishing
Date: 11-2000
DOI: 10.1063/1.1319982
Abstract: The methodology for accurately calibrating the Niobe resonant-mass gravitational wave detector is presented. The transducer is based on a low noise resonant microwave cavity transducer that converts the displacement of the resonating mass to microwave energy. The calibration technique consists of a one off measurement of the microwave frequency versus resonant-mass displacement characteristic. To measure this accurately, known static forces were applied to the resonant mass and the change in the transducer microwave frequency was recorded. With the aid of finite element analysis and accurate measurements of the resonant-mass characteristics, the deflection due to the known force was calculated. The calculated deflections were verified coarsely with measurements from a calibrated linear variable differential transformer. Typically, the detector operates with a 1 mK noise temperature. A best noise temperature of 890 μK between 1300 and 2000 Universal Time Coordinate (UTC) for day 60 in 1997 is reported. The transducer has been upgraded with a new microwave lifier, which has a measured electronic noise floor 40 dB lower than the previous lifier, which is only 10 dB above the quantum limit.
Publisher: IOP Publishing
Date: 12-03-2002
Publisher: American Chemical Society (ACS)
Date: 09-10-2015
Publisher: IEEE
Date: 04-2009
Publisher: Optica Publishing Group
Date: 16-11-2009
DOI: 10.1364/OE.17.021935
Publisher: IOP Publishing
Date: 19-03-2002
Publisher: American Physical Society (APS)
Date: 11-12-2000
Publisher: IEEE
Date: 2005
Publisher: IOP Publishing
Date: 16-09-2004
Publisher: AIP Publishing
Date: 13-11-2006
DOI: 10.1063/1.2387969
Abstract: The authors report on the development of a sapphire cryogenic microwave resonator oscillator with long-term fractional frequency stability of 2×10−17√τ for integration times τ& s and a negative drift of about 2.2×10−15∕day. The short-term frequency instability of the oscillator is highly reproducible and also state of the art: 5.6×10−16 for an integration time of τ≈20s.
Publisher: Institution of Engineering and Technology (IET)
Date: 2002
DOI: 10.1049/EL:20020670
Publisher: American Physical Society (APS)
Date: 21-07-2005
Publisher: Optica Publishing Group
Date: 27-03-2009
DOI: 10.1364/OE.17.005897
Abstract: There is great interest in developing high performance optical frequency metrology based around mode-locked fibre lasers because of their low cost, small size and long-term turnkey operation when compared to the solid-state alternative. We present a method for stabilising the offset frequency of a fibre-based laser comb using a 2 f - 3 f technique based around a unique fibre that exhibits strong resonant dispersive wave emission. This fibre requires lower power than conventional highly non-linear fibre to generate a suitable signal for offset frequency stabilisation and this in turn avoids the complexity of additional nonlinear steps. We generate an offset frequency signal from the mixing of a wavelength-shifted second harmonic comb with a third harmonic of the comb. Additionally, we have stabilised the repetition rate of the laser to a level better than 10(-14)/ radicaltau , limited by the measurement system noise floor.We present the means for complete and precise measurement of the transfer function of the laser frequency controls.
Publisher: Springer Science and Business Media LLC
Date: 09-2016
Publisher: American Physical Society (APS)
Date: 04-10-2006
Publisher: SPIE
Date: 08-09-2011
DOI: 10.1117/12.892887
Publisher: IOP Publishing
Date: 26-03-2004
Location: Japan
No related grants have been discovered for Clayton Locke.